In recent years, there is proposed a vehicular seat arranged attachably and detachably to a floor in order to realize an inner vehicle space rich in a variety pertinently in accordance with a mode of use, an object of use or the like. For example, in JP-A-2004-338576, in order to ensure a walk through space in a front and rear direction in a vehicle, in second seats (second row seats) for three person's seats, a center seat is made to be attachable and detachable. Specifically, a seat base is constituted by seat legs comprising left and right stand frames, and a bottom frame hung over between upper portions of the stand frames, and by providing lock apparatus engaged with strikers arranged on a floor at lower faces of the left and right stand frames, the seat base is made to be attachable and detachable to and from the floor. Further, the seat base is made to be able to be folded. A seat cushion as a seating portion is mounted attachably and detachably on the bottom frame, and when the seat cushion is detached from the bottom frame, a seat back as a back rest is made to be able to be folded onto the bottom frame. Further, the center seat detached from the strikers on the floor and made to be compact by folding the seat base and the seat back is stored inside of a trunk room formed by recessing the floor between first seats (first row seats) and second seats (second row seats), or stored in a space downward from a bench seat of a third row.
However, the storing space of the center seat according to JP-A-2004-338576 is simply provided with a shape and a size capable of storing the center seat, and a structure fixing the center seat is not particularly provided. Under the circumstance, the center seat is rattled by a vibration or the like when running a vehicle, interference sound is emitted by colliding with a wall face of the storing space at that occasion, and an unpleasant feeling is given to a passenger. Although, when stored inside of the trunk room recessed to the floor, the center seat can be prevented from jumping out by arranging a lid at an upper face thereof, since fixing means is not provided, emittance of interference sound is unavoidable.
Thus, there is a need in the art to effectively restrain emittance of interference sound at inside of a storing space when a vehicular seat attachable and detachable to and from a support base is stored inside a predetermined storing space.